Arterial Coordinated Signal Control Optimization Based On License Plate Data

Traffic congestion has increasingly become a critical traffic problem faced by big cities in China,causing inconvenience to people daily travel.Coordinated signal control carried out on arterials is an effective way to alleviate traffic congestion,and cycle and offset are main parameters for coordinated signal control,but coordinated control based on fixed flow and travel time did get an expected result because of the fluctuation of traffic condition in reality.With rapid development of vehicle identification and telecommunication technology,high-precision image data and processed vehicle information data are easily obtained from the database,which can provide real-time traffic data for arterials coordinated control and develop adequate and feasible coordinated schemes according to different traffic states and then effectively improve road capacity and alleviate traffic congestion.This paper first preprocesses the license plate data and extracts traffic parameters such as real-time traffic flow and travel time based on the license plate data.With the minimum traffic delay and vehicle stops as the optimization goal,the vehicle discrete model is established according to the upstream vehicle discharge and vehicle travel time distribution,and the traffic delay and vehicle stops are predicted further.Secondly,by means of the travel time with non-traffic signal delay,the Markov chain model and the time series method are used to optimize the cycle and offset respectively,and with the preset of minimum and maximum green time and phase sequence,the dynamic programming theory is used to solve the optimization goal.Finally,the optimization method is verified by taking 5 consecutive intersections of Jingshi Road and simulating on SUMO software.The results show that the average traffic delay and the average stops are reduced by 18% and 16% respectively in the coordinated phase compared with the real world and the graphical method.In the uncoordinated phase,the results are roughly the same as the graphical method,which is 9% lower than the real world.This effective use of license plate data provides a new perspective for designing offset and cycle of coordinated signal control plans.